1. Field of the Invention
The present invention relates to a sensor apparatus equipped with a touch panel, and an electronic apparatus.
2. Description of the Related Art
From the past, as an electronic apparatus such as a personal computer, there is known an electronic apparatus that is equipped with a touchpad. Regarding such an electronic apparatus, an input operation is made by pressing a touch surface of the touchpad using a finger or a touch pen and detecting a position pressed by the finger or the like. For example, Japanese Patent Application Laid-open No. Hei 10-198503 (FIG. 2 etc.) (hereinafter, referred to as Patent Document 1) discloses a touchpad that uses a variable capacitor to measure a position and amount of a force applied to a touch surface.
In the touchpad disclosed in Patent Document 1, one of two plates (electrodes) of the variable capacitor is provided on a flat top member that supports the touch surface. The other plate is provided on a reference frame that forms a frame of the touchpad. The flat top member and the reference frame are coupled via a plurality of springs, and the two plates are provided so as to oppose each other.
The pressed touch surface moves in a pressing direction and returns to its original position by an elastic force of the springs. At this time, a distance between the two plates of the variable capacitor changes to thus change a capacitance of the variable capacitor. Based on the capacitance change, a position and amount of a force applied to the touch surface are measured.